When each bond matures, you replace it with another one of the same maturity.

A laddered portfolio protects you in all interest-rate scenarios. When rates are rising you will re-invest the money from your maturing bonds at higher rates.

And when rates are falling, your long-term bonds will still be paying you interest at the higher rates prevailing when you bought them.

Some economists think the Federal Reserve may have to push rates up soon, while others see another easing operation as the central bank’s next move. A laddered bond portfolio provides a margin of safety in either case.

If you don’t have $500,000 or so to put to work, and you don’t want to stick with Treasurys in your ladder, you’re probably best off purchasing mutual funds and/or exchange-traded funds, financial advisers say.